If a host is nonoperational, for example, due to hardware failure, recover the segments onto a spare set of hardware resources. If mirroring is enabled, you can recover a segment instance from its mirror onto an alternate host using the gprecoverseg utility. For example:

$ gprecoverseg -i recover_config_file
      

Where the format of the recover_config_file file is:

<failed_host>|<port>|<data_dir>[ <recovery_host>|<port>|<recovery_data_dir>]

For example, to recover to a different host than the failed host without additional tablespaces configured (besides the default pg_system tablespace):

sdw1-1|50001|/data1/mirror/gpseg16 sdw4-1|50001|/data1/recover1/gpseg16

For information about creating a segment instance recovery file, see gprecoverseg.

The new recovery segment host must be pre-installed with the Greenplum Database software and configured exactly as the existing segment hosts.